The present invention relates to an apparatus for reproducing information, and more particularly to an apparatus for reproducing digital audio information, especially for playing back pre-recorded musical accompaniments, so-called "karaoke".
A conventional apparatus for playing back pre-recorded musical accompaniments, or a musical accompaniment playback apparatus, reproduces such pre-recorded musical accompaniments by playing back information recording mediums, such as magnetic tapes video disks, etc., on which only musical accompaniments are recorded. Such a musical accompaniment playback apparatus includes an amplifier connected to a microphone and a loudspeaker, and mixes vocal signals supplied from the microphone with signals of reproduced musical accompaniments, amplifies the mixed signals, and supplies the amplified signals to the loudspeaker to produce audible sounds.
Sometimes, a user of the musical accompaniment playback apparatus may be desirous of playing back and singing the latter half of a music piece or song or a certain portion of the music piece repeatedly several times. It would be convenient if any desired portion of a music piece or song can be played back repeatedly.
Recently, compact disks (CDs), which are one type of digital audio disks, are used as a recording medium for karaoke music or musical accompaniments. On a CD, pulse-code-modulated musical information is recorded in time-divided storage areas. Code information, referred to as a "subcode", is recorded at the leading end of each of the storage areas. One of the innovative features of the CDs is that any desired music piece recorded on a CD can quickly be selected or accessed by searching the subcodes on the CD at high speed. One storage area, known as "TOC" (Table of Contents) and serving as a table of subcodes for retrieving recorded music pieces, is located on the innermost track of the CD, called "lead-in area", which is read first at the playback. The TOC storage area has a storage capacity of 9 bytes. When a CD is loaded in a CD player, the CD player reads the data of the TOC on the CD. The user inputs a control command indicative of the subcode corresponding to the leading end of a desired music piece recorded on the CD. Then, the CD player searches for an address having the indicated subcode on the CD, and moves an optical pickup to a radial position on the CD which corresponds to the address. When the optical pickup reaches the addressed position, it starts to reproduce the music information from the address.
The TOC storage area can store only information about time periods from the start of the music pieces, addresses of the time-divided storage areas or sections, etc. because of the limited storage capacity. The storage capacity of the TOC storage area is not large enough to store any data that would interconnect the words of the recorded music pieces or songs and the addresses. Accordingly, the CD player cannot start playing back the CD from the position of any desired word of the song.